题目： Improving ionic/electronic conductivity of MoS2Li-ion anode via manganese doping and structural optimization
作者： Jiacheng Wang1，Liyang Zhang1，Kuan Sun1，Junjie He2*，Yujie Zheng1，Chaohe Xu1, Yuxin Zhang1，Yu Chen3*，Meng Li1*
单位： 1. MOE Key Laboratory of Low-grade Energy Utilization Technologies and Systems, CQU-NUS Renewable Energy Materials & Devices Joint Laboratory, School of Energy & Power Engineering, Chongqing University, Chongqing 400044, China
2. School of Science, Chongqing University of Posts and Telecommunications, Chongqing 400065, China
3. School of Optoelectronic Science and Engineering & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, China
摘要： Developing anode materials for lithium-ion batteries with excellent electrochemical performance is crucial to satisfy the requirement for energy storage. Molybdenum disulfide is recognized as a prospective anode material due to its high theoretical capacity and two-dimensional layered structure. However, its further application is mainly hindered by its poor electronic conductivity. Herein, we report Mn-doped MoS2 nanosheets anchored on hierarchical carbon skeleton (MMSC) acting as an anode material. The as-synthesized electrode exhibits a high initial discharge capacity of 1280mAhg−1 at a current density of 0.1Ag−1, high rate capacity (920mAhg−1 at 2Ag−1), and long-time cycling stability (71% capacity retention after 1000 cycle). Compared to that of pristine MoS2 electrode, the improved performance of MMSC anode can be attributed to the synergetic effects of optimized composite structure and Mn doping. The hierarchical carbon skeleton provides a larger surface area, allowing effective electrolyte penetration and preventing aggregation of MoS2 nanosheets in charge/discharge cycles. To further understand the mechanism of the improved rate capability, calculation of corresponding atomic models according to experimental results and first-principles calculation are conducted. The calculated results prove that the Mn-doped MoS2(MMS) has a lower diffusion barrier of Li+ than that in pristine MoS2. Moreover, the as-synthesized MMSC electrode also demonstrates better electronic conductivity because of the electronic injection by Mn atoms.